Apparatus for processing sheets to be used in can making



Jan. 19, 1932. P. KRUSE 1,341,324

APPARATUS FOR PROCESSING SHEETS TO BE USED IN CAN MAKING Filed April 22. 1927 3 Sheets-Sheet 1 53 ziwza (g,

3 I :INVENTOR +1 flea! W, By Attorneys, 7

P. KRUSE 1,841,824

APPARATUS FOR PROCESSING SHEETS TO BE USED IN CAN MA KING Jan. 19, 1932.

Filed April 22. 1927 3 Sheets-Sheet 2 1/ sV// W W ll P. KRUSE Jan. 19, 1932 APPARATUS FOR PROCESSING SHEETS TO BE USED IN CAN MAKING Filed April 22 1927 3 Shets-Sheet 5 By Attomey,

035 0C0, llllllllll a 0 e56: Pb onn a v a Q o a o o o a a a HBIQGBEDIQIDGI Tmw m Patented Jan. 19, 1932 UNITED STATES PATENT OFFICE PETER KRUSE, OR BROOKLYN, NEW YORK, ASSIGNOR TO E. W. BLISS COMPANY, OF

. BROOKLYN, NEW YORK, A CORPORATION OF DELAWARE APPARATUSIOR PROCESSING SHEETS TO BE USED IN OAN MAKING Application filed April 22,

This invention relates to apparatus for treating or processing sheet metal which is to be employed in the making of round can bodies. In the making of tin cans it is usual to use commercial tinned plate, made commonly of open hearth steel, the softness of which occasions difiiculty in the making of round can bodies, as will be made apparent hereinafter.

The object of this invention is to provide apparatus whereby the physical properties of sheet metal may be altered so that such metal will more-readily conform to the desired shape of can bodies when made into such bodies by the body-making machinery now in general use.

Another object of the invention is to provide an apparatus which will change the physical properties of sheet metal and out said sheets into desired shapes in a single continuous operation whereby improved blanks of the required shape for use in can bodymaking machineswill be delivered fullyprocessed according to my method, so that these improved blanks may be lmmediately put through the body-making machines.

This invention also contemplates a device which is adapted to produce sheets having more nearly uniform physical properties as compared with other sheets of the same' or an entirely different lot of material; and the novel'method whereby this result is accomplished is in itself an object of the present invention.

A further object of the invention is to provide a novel drive for a plurality of sheet processing rolls whereby said rolls may be positively driven and at the same time be susceptible of transverse adjustment, such adjustment permitting of varying the cooperative effect of the rolls upon the sheets.

This invention also provides a combination slitting and sheet processing device in which the section of the device carrying the processing rolls may be readily shifted to permit the use of the slitter independently of the processing rolls, yet at the same time preserving the relative adjustment of the said rolls.

Other objects of the invention will be set 1927. Serial No. 185,790.

forth in connection with the detailed description hereinafter to be given.

The problem which has been solved by the present invention is one which has caused a great deal ofdifiiculty in the can making art. With the can body-making machines now in general use, it has been found that although the body blanks are wrapped around forming horns which may have, for example, perfectly smooth round contours, the can body when finished, far from presenting a smooth round surface, shows a certain number of-flattened areas, these areas attimes extending in a series completely around the can body. Many of these cans are so deformed as to give the impression that they have been deliberately made polygonal or many-sided, instead of 'as true cylinders. The number of the fiat faces which appear seems to be determined largely by the physical properties of the particular kind of sheet employed. Furthermore, the grade of sheet material gen-' erally preferred by the can maiuifacturers because of its free drawing properties which facilitate the flanging and seaming opera tion, is always the material most subject to the tendency to develop flattened areas when wrapped around the horn in the usual bodyforming machine.

Certain types of material. such as Bessemer sheet, are not so subject to the difiiculty above A point is soon reached, however, at which the stress exceeds the elastic limit of the material and the sheet is sharply bcnt and re- .ceives a permanent deformation. By this permanent deformation the stress in the remaining portion of the sheet is partially relieved, and as a consequence of this, the mal terial will again be wrapped a certain further distance around the horn, but without being stressed beyond its elastic limit. Again, how ever, a point is shortly reached at which the stresses exceed the elastic limit and the sheet takes on a second set or deformation, this latter deformation occurring at a point angularly removed from the first described deformation; and this same process goes on completely around the body-forming horn so that the can body, when completed, exhibits oftentimes as many as a dozen flat surfaces,

or more.

The tendency of the sheets to form flat surfaces when wrapped about the body-forming horn is practically eliminated by processing the sheet metal according to the present invention. By this process the sheet material is subjected to a series of bending stresses first in one direction and then in another, the sheets being preferably passed through' a series of staggered bending rolls which cause the sheet to be bent in a series of waves, the position of the waves continuously shifting along the sheet as it is passed through the rolls so that every part of the sheet is subjccted to bending stresses in alternate directions a number of times. This particular method of processing the sheets, when properly employed, has the additional advantage of rendering more nearly uniform the physical properties of sheets, which, originally as they come from the sheet mills, may differ widely.

The sheets or blanks having been processed in the manner thus described are thereupon made up into rounded can bodies of cylindrical, oval, or other such form, by bending around a horn or mandrel in the customary manner. As apparatus for this purpose are well-known, it is unnecessary for me to illustrate such apparatus in the present application, but reference may be made to my Patents, No. 1,046,088, dated December 3, 1912., and No. 1,569,093, dated January 12, 1926, for illustrations of examples of suitable body forming mechanism.

To bring sheets having different physical properties to substantially a common standard according to my process, the bending rolls are preferably adjusted so that they will stress the sheet metal as it enters the series of rolls somewhat beyond the elastic limit of the softer metal, bending the sheet first in one direction and then the other and effecting a succession of permanent deformations in the sheet. By a series of such opposite deformations, it appears that the elastic limit of the metal is increased, because in passing through the last end rolls of the series, the sheet in its altered condition, though stressed by such rolls sufficiently to acquire a permanent deformation if it were possessed of only its initial elastic limit, will not be permanently deformed by such end rolls. The apparatus therefore may be employed to render more uniform the elastic limit of sheet metal, because sheets which have an initially high elastic limit upon entering the. series of rolls may not be permanently deformed at all and will pass through the rolls substantially without change, whereas sheets which have a low elastic limit to start with will be permanently deformed a number of times until their elastic limit has been elevated to a point at which passage through subsequent rolls no longer results in permanent deformation of the material. At such time the elastic limit of the material has been brought closer to the desired standard. It may require only a single bend or two with some materials, and perhaps half a dozen bends with sheets having different properties, but eventually by this process the sheets will he brought to substantially a standard, and thereafter subsequent passage through succeeding rolls will not alter the elastic limit of the material.

To attain a high output efiicicncy in the production of blanks suitable for the making of can bodies, the present invention provides in combination with the processing rolls above referred to, a gang slitting device which divides the large sheets into strips of suitable width for the making of can bodies. Only a single feed mechanism is required for this combination apparatus, the sheets being cut to size and processed according to the present invention in a single continuous operation, and delivered from the machine as blanks of correct size possessing improved physical properties better adapted to be used in the usual can body-making machine.

The invention will now be described in detail, reference being had to the accompanying drawings in which like reference characters refer to corresponding elements in the diflerent views, wherein Figure 1 is a plan view of the sheet processing device showing the rotary cutters and the series of bending rolls as they appear viewed from above.

Fig. 2 is a vertical cross-section of the mechanism shown in Figure 1 taken along the broken section line 11-11.

Fig.3 is a side elevation of the same mechanism illustrated in Figs. 1 and 2, the view being taken from the opposite side of the machine as compared with the view shown in Fig. 2.

Fig. 4 is a vertical cross-section taken through the. axial centers of the right hand pair of bending rolls, as indicated by the section line IV-IV in Fig. 2.

Fig. 5 shows diagrammatically an elementary method of processin sheets according to the present invention.

Fig. 6 illustrates diagrammatically the method of processing sheet metal by the use of the machine illustrated in Figs. 1 to 4 inclusive.

My invention in its preferred embodiment as an apparatus comprises the combined slitting and bending device illustrated in the several figures, although it will be obvious that the apparatus for altering the physical properties of sheet metal may be used independently of, or entirely severed from, the cutting or slitting mechanism which divides the large sheets into strips of suitable width for the making of can bodies. As shown in Figs. 1 and 2, the sheet cutting mechanism generally referred to by the letter A is situated at the left hand endof the apparatus.

This cutting mechanism isof the conventional type employing a gang of upper and lower rotary cutters or shears, respectively designated 1, 1. The sheet metal is shown at 2. This sheet, in passingthrough the gang slitter A, is divided into a number of strips which are fed directly from the cutters 1, 1 into the processing or bending rolls, this latter part of the mechanism being referred to generally by B.

Any suitable feed device, either manual or automatic, may be employed for feeding the sheet metal into the gang slitting end of the apparatus. Reciprocating feed bars 3, the upwardlyprojecting sheet engaging elements 3 of which are schematically indicated to the left of sheet 2, may be employed. The details of such a feed mechanism are set forth in my United States Patent No. 1,433,138, granted October 24, 1922, this patent also showing the general arrangement of the vari ous parts of the gang slitter.

The sheet bending apparatus B comprises preferably a frame 10 which is supported by the frame 11 of the gang slitter A. The connection between the two frames at the top may comprise a hinge-like support 12 whereby the sheet bending or treating apparatus may be swung upward out of the path of the sheets as they come out of the gang slitter,

so that the slitter may be used independently. When the sheet treating apparatus is in operative position and swung down in line with the gang slitter, it is held rigidly in position by means of screws 14 which pass through a flange at the lower part of the frame 10 directly into the vertical end mem-.

bers of the frame 11.

Within the frame 1.0 is mounted a series of bending rolls, the upper rolls 20 and lower rolls 21 being so disposed with respect to each other that the sheet metal 2 in passing between them will be bent alternately up and down in a series of wave-like bends, as indicated in Fig. 2. With the exception of the two end pairs, the rolls are each preferably mounted for free rotation in independently adjustable bearing blocks 22, 23. These blocks are slidably carried upon upper and lower guideways 24, 25, respectively formed in the frame 10, and are adapted to be adusted longitudinally of the frame so that the center distance of the rolls 20, 21 may be varied.

The end bearing blocks 22, 23- are securely clamped in adjusted position by-screws 26 .which pass freely through slots 27 in frame 10 and screw into the blocks. When .the screws are tightened, the blocks are drawn securely against the guideways on which they ride. As the primary function of the rolls 20, 21 is merely to impart a series of bending stresses to the sheet metal, it is obvious that the rolls need not be adjusted so close as to apply any pressure to the metal as it passes between pairs of rolls. The rolls serve primarily as guides whereby the sheet is alternately directed upwards and downwards at an angle suflicient originally to produce permanent deformations in the material of the sheet.

posite ends of the roll which they support.

The pressure between the two rolls may be Varied by adjusting the screw blocks 33 which bear against tensioning springs 30. A simi lar mounting for the upper roll at the right hand end of Fig. 2 may be provided whereby to apply pressure between the end rolls which deliver the strips of sheet to a collecting table after the sheets have been processed. The U-shaped guides, however, for the vertically adjustable end bearing blocks 33 are formed integrally with the blocks 34 which support the lower end roll. These blocks 34 slide longitudinally of frame 10 in guideways 25, being adjusted by means of screws 35 which pass through the vertical end walls 36 of frame 10 and are threaded into blocks 34. The blocks are held fast in adjusted position .hy means of two screws 37 which clamp the blocks securely against the frame members on which they ride. The upper and lower right hand rolls 20, 21 are provided with a common bearing support 34 for the reason that these two rolls, unlike any of the others, are connected together for common rotation by gears 40 and 41 respectively, which are carried at the right hand side of the machine (as viewed from the feed end of the machine, i. e., the end at which the gang slitting mechanism is located). These gears are best seen in Fig. 4.

In Fig. 4 there are also illustrated the constructional details of the rolls and their end bearings. In the preferred embodiment of my invention the rolls 20, 21 are preferably formed of hollow tubing, a cylindrical block 42 being inserted at either end to reinforce the tube and also to provide a rigid spindle -13 which projects through the bearing blocks and receives at its outer end the drive, either through gearing or by means of a chain and sprocket drive, as will be hereinafter explained. The block l2 may be. welded into the tubular rolls or it may be fastened therein by means of pins a l.

The upper and lower rolls, with the exception of the last upper roll, are respectively provided at their left hand ends (as viewed from the feed end of the machine) with sprocket wheels 50, 51 (see Fig. 3). These sprockets are all of the same diameter and are rotated by a single continuous chain 52 which when the rolls are properly adjusted passes between the upper sprockets 50 and the. lower sprockets 51 in a series of slight undulations so that the chain will be held in secure driving contact with the sprocket teeth. This chain passes around the two end sprockets and underneath a vertically adjustable idler 53 to form a continuous loop. By this arrangement the upper and lower rolls are rotated at the same speed and in opposite directions, so that the sheet material will be acted upon by each roll in such H1311- ner as to advance it through the apparatus. The shaft or spindle 43 of the last lower end roll. and upon which shaft is rigidly mounted the sprocket 51, receives its drive from chain and sprocket drive 55, 56 and 57, the sprocket so being rigidly mounted on spindle -13. The. driving sprocket 57 which supplies power to the rolls through chain and sprocket 56 is preferably mounted rigidl v upon the lower shaft 58 of the gang slitter and is so proportioned with respect to sprocket fit; that the rotary cutters 1, 1 and rolls 20, 21 willhave substantially the same peripheral speed. The gang slitter A is driven by means of a pulley 60, shown fragmentarily at the top of Fig. 1, this pulley being keyed to the shaft 58 at the same end and outside. of sprocket 57. The reverse gears 61 by which the upper and lower cutter shafts of the gang slitter A are commonly rotated lie between the sprocket 57 and pulley 60. By this grouping of the driving pulley, reverse g ars and roller driving sprocket, the shaft 58 of the gang slitter is relieved of all strain other than that required for the actual cutting of the sheet metal except over the very short length required to support the aforesaid pulley, gear and sprocket at one end.

The tension of chain 55 may be adjusted by means of screws 35, which, as before set forth, cause the slidable end bearing blocks 34 to shift longitudinally of the frame 10.

The operation of the device is as follows: Sheet metal to be used in the making of can bodies is fed into the rotary cutters of the gang slitter A, either manually or automatically, the cutters having been adjusted to desired positions to produce strips of the desired width. As the sheets pass through the cutters they are fed directly to the series of sheet-treating rolls 2t), 21, where the strips are alternately bent, downward between the first two rolls, upward between the first upper roll and the. second lower roll, then downward again between the second upper roll and the second lower, again upward between the second upper roll and the third lower roll, etc. In practice it will be found that the rolls can be adjusted so that in spite of the fact that the sheets in passing through the first of the rolls will be stressed beyond their elastic limit and consequently permanently deformed, the subsequent rolls can be made to llatten the sheet out, so that when it is delivered from the last pair of rolls the sheet will again be substantially fiat. Any adjustment which will alter the axial distance between the rolls will obviously permit of their adjustment to impart a greater or lesser curvature to the sheets during the processing of the metal. However, in the present embodiment the rolls have been made horizontally adjustable, as hereinbefore explained. The degree of curvature that should be im parted to the sheets in processing them will vary with the material of which the sheets are made and also the gauge of the sheet.

The rolls should not be adjusted to subject the. sheets to excessive bending stresses but should be so arranged that the sheets are worked or processed by reverse bending operations just enough to cause such sheets to acquire properties which permit of the sheets being formed around the horn of can bodymaking machines Without developing flattened areas, heretofore explained, the ultimate object being to produce a smooth, round can body. The term round is used merely in the sense that the can body should have a smoothly curved contour; the can may actually be elliptical or of any other curved center.

It has been found advantageous in processing extremely soft sheets to run them through the rolls twice, the sheet being turned between the two operations so that the line of bending produced by the rolls during the second operation will be at right angles to the line of bending produced by the first operation. That is to say, the sheets will be first rolled crosswise and then lengthwise. Both of these processing operations may include the cutting of the sheet into smaller sizes, it be ing usual to first trim the edges of the raw sheet and at the. same time out the sheet into strips having a width sutlicient to form the eircun'ifcrence of the can body. These strips are then turned crosswise and run through the gang slitter, which cuts the strips into widths determined by the height of the can body which is to be formed. It is obvious that the apparatus hereinbefore described Or. n

and illustrated permits of the, trimming and slitting of sheets as above set forth, combining at the same time with each of these 0 rations a processing of the material b' a ternate reverse bending operations, the rst operation being carried out at right angles to the second.

If it is desired to use the gang slitter part of the apparatus without subjecting the sheets to the processing which occurs )etween the bending rolls, the frame 10 carrying such rolls may be swung about the pivotal support 12 and raised sufliciently to permit sheets of material to pass through the slitter without obstruction. If, on the other hand,it is desired to use the processing rolls to treat sheets of materials which are already of the correct size, the rotary cutters 1, 1 may be removed from the slitter, thereby permitting the sheets to pass freely into the section of the apparatus containing the processing rolls.

It will be borne in mind that while the apparatus hereinbefore described is particularly designed for the treatment or processing of sheet metal to be used in the making of can bodies, the treating of sheets by alternate bending operations may be carried out independently of this mechanism and in a reat variety of ways. By such means the physical properties of the sheets are altered to render such sheets more suitable for use in the making of can bodies in the usual bodymaking machinery, such machinery, as heretofore set forth, being characterized by bending wings or analogous elements which bend a sheet of metal around a mandrel or born, as it is termed in the art.

As illustrated diagrammatically in Fig. 5, a sheet of metal may be processed according to my method by simply bending the entire sheet to and fro from the normal position a, a alternately to the positions indicated by the dotted lines I), b and 0, 0. Such alternate bending may be accomplished by any known means and if performed a suiiicient number of times and in such manner as to stress the metal sheet beyond its elastic limit, will result in altering the physical properties of the sheet so that smooth, round can bodies may be formed therefrom on the usual can body-making machines. v

Fig. 6 diagrammatically illustrates the method as carried out by the particular apparatus hereinbefore described and illus* trated in Figs. 1 to 4. The-metal sheet 2 moving from left to right is alternately bent up and down by rollers 21, 20, the sheet emerging finally through the pair of rolls at the right which are preferably so adjusted that with respect to the other rolls that the normal sheet is restored to a substantially flat condition when the processing is complete. It is not necessary for the sheet to extend entirely through the series of processing the rolls in order to obtain a positive feed. In-

deed, if the sheet is only long enough to span the widest separated adjacent pair of upper or lower .rolls it will feed through the series of rolls automatically and solely through the tractive effort of the moving rolls. This traction of the rolls upon the sheet is not dependent upon the rolls being adjusted to ositively grip the sheet between them. uflicient traction is obtained even when the rolls are widely separated because of the pressure exerted against the rolls by the resistance of the sheet metal to bendin While onl a single emiodiment of my invention has een described and illustrated, it will be understood that the invention is not limited thereto but may be otherwise variously embodied and modified without departing from the spiritof the invention as set forth in the following claims.

It is to be understood that in using the term permanently deformed to express the effect of a sufiicient bending operation, I am using that term in its technical sense where it means a bending beyond the elastic limit of the metal, so that the sheet cannot immediately spring back to its original form, but instead acquires a set, retaining to some extent the bend imparted to it by the roller. This set endures only as long as the molecular change induced in the metal will last, and this period differs with different qualities or conditions of the metal of the sheets and may vary somewhat with any given lot or consignment of sheets. It is important for the full realization of the advantages of my invention that the final step of bending the processed sheet or blank into the cylindrical or other rounded form of the can body be performed before any perce tible molecular change from the set or de ormed condition may takeplace. It is preferable that the operation be substantially continuous as normally occurs in the due course of manufac- 1 ture.

What I claim is:

1. An apparatus for processing sheets to be used in the making of can bodies, said apparatus comprising rotary sheet slitting means, means adapted to advance a sheet through said sheet-slitting means, and sheet bending means, said sheet-slitting means being disposed relative to said sheet-bending means in a position to feed the strips into which the sheet is cut, directly into said sheet-bending means.

2. An apparatus for processing sheets to be used in the making of can bodies, said apparatus comprising a gang slitter having cooperating rotary shears adapted to divide a sheet into a plurality of strips of widths suitable for making can bodies, and a series of staggered sheet-bending rolls adapted to bend the material of said strips in opposite Ill directions whereby to alter the ph sical properties of said material, a pair 0 said has been release rolls being disposed with respect to the said gang slitter so that the distance between the mutual strip-engaging portion of said rolls and the mutual sheet-engaging portion of said rotar shears is less than the length of a strip w ereb the strips-will be engaged between the sai air of rolls before the sheet from between the said rotary shears so that the several strips will be automatically ganged through the bending rolls abreast.

3. An apparatus for processing sheets to be used in the making of can bodies, said up aratus comprising a series of staggered re s, said rolls being adjustably mounted to permit of varying the distance between the rolls, sprocket wheels in direct driving connection with said rolls, and an endless chain engaging said sprocket wheels, said chain passing alternately over and under the sprockets in the series whereby the upper sprockets will be rotated oppositely to the lower sprockets.

4. The apparatus according to claim 2,

further characterized in that the bending rolls are operatively connected to the drive a of the gang slitter, the driving ratio between the rolls and the slitter being such that the surface speed of the rolls at least e uals the s eed of the sheet material as it is ed from t 1e slitter.

5. The apparatus according to claim 2, further characterized in that a frame is providedto carry said series of sheet-bending rolls, said frame being pivotally mounted adjacent to the said gang slitter, the pivotal motion of said frame permitting the rolls to be swung out of the path of the strips as they are delivered from said slitter when it is desired to use the slitter independently of the processing rolls.

In witness whereof, I have hereunto signed my name.

PETER KRUSE. 

